Q1: Which effect of electric current is utilized for detecting the flow of current through a solution when a compass is used?
Q2: What is meant by the chemical effect of electric current? Give an example.
Why is electroplating useful?
Q3: A beaker contains an acidified copper sulphate solution. A copper plate and a carbon rod are kept in this copper sulphate solution. The copper plate is connected to the positive terminal of a battery whereas the carbon rod is connected to the negative terminal of the battery. What happens when electric current is passed through copper sulphate solution?
Q4: Name two metals which are usually electroplated on cheaper metals for making jewelry (or ornaments).
Q5: Why the bulb glows when the electric current passes through it?
Q6: Tap water conducts electricity whereas distilled water does not. Give reason.
Q7: The process that you saw in Activity 14.7 is used for purification of copper. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. Copper from impure rod is sought to be transferred to the thin copper plate. Which electrode should be attached to the positive terminal of battery and why?
Q8: Does pure water conduct electricity? If not, what can we do to make it conducting?
Q9: In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area. Explain why they do this.
Q10: What happens when electric current is passed through acidified water?
Q11: A child staying in a coastal region tests the drinking water and also the seawater with his tester. He finds that the compass needle deflects more in the case of seawater. Can you explain the reason?
Q12: What is the advantage of using LED in testing the electrical conductivity of liquids?
Q13: For electroplating copper on an iron object, which terminal of the battery (positive or negative) is connected to the iron object?
Q14: Is it safe for the electrician to carry out electrical repairs outdoors during heavy downpour? Explain.
Q15: Which is the polluting waste generated by electroplating factories?
You can find Worksheets Solutions here: Worksheet Solutions: Chemical Effects of Electric Current
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1. What are the chemical effects of electric current? |
2. How does an electric current cause electrolysis? |
3. What is electroplating? |
4. How is electroplating useful in everyday life? |
5. What is the role of electrodes in the chemical effects of electric current? |
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